The present invention relates to a door lock, which automatically forces the latch bolt forwards after unlocking, and automatically locks the door after closing of the door.
FIG. 1 shows a door lock according to U.S. Pat. No. #5,176,416 (issued on Jan. 5, 1993). According to this structure of door lock, the latch bolt is at the unlocking status when the door lock is unlocked. When returned the home and opened the door, the door lock must be locked again after closing of the door. If the door lock is not locked after closing of the door, an intruder can directly open the door and enter the house.